Processing of fore-ends in the boning rooms of slaughterhouses comprises a long series of manual operations, the purpose of which is to remove bones, cartilage and sinews, and which serves to separate and trim the muscles. The operations require experienced operators in order to achieve a good meat yield. The work is a strain on the operators, especially the removal of the internal bones. There has long been a need for a mechanization of the process, but the auxiliary apparatuses known up to now can only be used for removal of single bones and therefore the processing is still highly demanding for the operators.
There exist for example machines and apparatuses, which can extract a shoulder blade. DK 144.404 B (Slagteriernes Forskningsinstitut) describes an apparatus, which extracts the shoulder blade from a bacon side by means of a hook. First, a manual separation is performed between the humerus bone and the shoulder blade. Then, the shoulder blade is extracted in the longitudinal direction of the blade, so that the shoulder blade pocket remains intact, which is important by bacon sides. EP 0468 010 B1 (Slagteriernes Forskningsinstitut) describes an apparatus for extraction of the shoulder blade from a fore-end, which is to be separated into meat parts. The apparatus extracts the shoulder blade by means of a hook. The extraction is performed in a direction at right angles to the plane of the shoulder blade.
EP 0832 563 B1 (Slagteriernes Forskningsinstitut) suggests an automated, partial boning of fore-ends by first fixing the fore-end and then cutting the bones completely or partially free from the meat. It is suggested to remove the shank bone and the shoulder blade and partially loosening the humerus bone from a fore-end by fixing the fore-end, determining an anatomical fixed point and moving a gripper in to this part of the bone, which is to be removed. After the gripper has gripped around the bone, a cutting operation is performed along the bone guided by this by means of tools on the gripper. The disadvantage of this known technique is that each individual fore-end has to be fixed before the gripper are activated and that the tools has to be used each one individually on the fixed fore-end. The result of this is a poor coefficient of utilization of each individual tool and it makes the process fairly slow.
The only apparatus known today that can bone fore-ends without surface bone in one process uses a press with two matrices, which squeezes the meat away from the shoulder blade, the shank bone and the humerus bone. Most slaughterhouses prefer to maintain the manual boning, as the apparatus damages the meat structure, resulting in meat of a reduced value. Furthermore, there will be splinters of bone in the meat.
Thus, the problem with the known apparatuses and methods is that they cannot perform a boning operation of fore-ends at a high speed and with good utilization of tools if an acceptable meat quality after the boning operation is to be achieved.